Orthopedic pad

ABSTRACT

A lumbosacral support system having a belt and an orthopedic pad carried by the belt. The pad has a contoured template surface with a transversely extending central trough portion for accommodating the protruding spinal processes of the wearer when the pad is pressed against the lumbar region, and a pair of raised plateau regions flanking the central trough portion for contacting the erector spinae muscles of the wearer to provide support. The template surface of the pad has a vertical surface contour through the central region approximating the average lordotic curve of a wearer. The belt is longitudinally tapered so the pad is arranged at an angle to vertical to optimally engage the lumbar region of the wearer.

This is a Continuation of application Ser. No. 07/933,437, filed Aug.20, 1992, now abandoned.

BACKGROUND OF THE INVENTION

This invention relates to orthopedic devices of the type used to providesupport for the lower back. More particularly, this invention relates toan orthopedic device in the form of a belt adapted to be worn by a userand to provide support for the lower back of the user.

Many orthopedic devices have been proposed, the purpose of which is toprovide lower back support to prevent or alleviate lower back pain.Belts designed for this purpose have generally been of two differenttypes. A first type uses some type of conforming pad, typically made ofa foam material, with the pad being permanently attached to the belteither inside or outside the fabric comprising the belt, with the pad ina position to be compressed against the lower back region when the beltis arranged about the waist of the user. The second type of deviceemploys an inflatable air bladder having one or more air chambers, thewall of the bladder being sufficiently flexible to enable the airchamber to conform to the shape of the back of the wearer when the beltis attached around the waist. Both types of device suffer from thedisadvantage that the portion of the device in contact with the back ofthe user (i.e., the pad or the air chamber walls) functions to easilyconform to the shape of the wearer's back. Consequently, if the lowerback is in a position other than the ideal posture, the belt does notpromote a change to the proper posture since the contact region of thepad adapts to the shape of the lower back. When this shape is contorted,as for example by performing a stressful lifting routine, the back isnot effectively impeded by the device from maneuvering to an improperposture. Efforts to date to design an orthopedic device devoid of thesedisadvantages have not been successful.

SUMMARY OF THE INVENTION

The invention comprises an orthopedic device which provides yieldablebut substantial resistive force to the lower back region of the user sothat this region is provided with an idealized contoured template.

A belt is provided with an orthopedic pad at essentially the mid-pointof the length of the belt, the pad being preferably confined within aspace enclosed by a suitable belt fabric such as nylon or the like. Theorthopedic pad has an essentially planar base facing away from the backof the user when the belt is installed and an orthopedic templatesurface having a compound configuration. The perimeter of the orthopedicpad comprises two essentially straight edge portions at opposing endsthereof, and a pair of curved edges extending therebetween. Each curvededge has a convex shape with the maximum outward excursion atessentially the mid-point of the curve. The template surface of theorthopedic pad has a centrally located hollow region extendingtransversely of the mid-point thereof, the hollow region being flankedby substantially flat surface regions extending away from the hollowregion and gradually descending to flanking valley regions which blendsmoothly into the lateral edges of the pad. A portion of the templatesurface approximates the average lordotic curve of a wearer. The pad ispreferably perforated in several spots in order to provide ventilationthrough the pad. The pad is fabricated from a relatively stiff butresilient material which provides non-conforming yieldable support forthe lower back region of the wearer.

The belt has a longitudinal dimension along the top edge thereof whichis shorter than the longitudinal dimension along the bottom so that thepad is tilted slightly forwardly when arranged about the waist of theuser. This optimizes the angular position of the template surfaceagainst the lower back region and accounts for the normal waist and hipmeasurement differential encountered in users, thereby providingsubstantially equal intra-abdominal pressure to all parts of theabdomen.

In use, the belt is installed around the waist of the user with theorthopedic pad in contact with the lower back region. When arrangedproperly along the lower back region, the high points on the templatesurface of the pad contact the erector spinae muscles alongsubstantially parallel paths with respect to the spine to provide aresistive but yieldable support surface. Thus, any tendency of the lowerback region to extend out of the idealized configuration represented bythe template surface is opposed by the orthopedic pad. In addition,flexion is opposed by the natural tendency of the proprioceptors of theback (which comprise muscles, ligaments and nerves) to adapt to andfollow a smooth firm surface. In addition, during muscle relaxation thepad tends to move away from the spine as an integral unit, which allowsthe muscle and ligament structure to provide its own support. This tendsto substantially reduce or eliminate atrophy of the back muscles.

In an alternate embodiment of the invention, the belt is provided with aplurality of secondary belt loops which can be used to support varioustool holders of the type used by workmen. Thus, the belt can be adaptedfor use in a wide variety of occupations while providing the orthopedicbenefit.

For a fuller understanding of the nature and advantages of theinvention, reference should be had to the ensuing detailed descriptiontaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a first embodiment of theinvention with the belt partially closed;

FIG. 2 is a side sectional view taken along lines 2--2 of FIG. 1 andillustrating the pad in place against the lower back region;

FIG. 3 is a plan view of the template surface of the orthopedic pad;

FIG. 4 is a sectional view taken along lines 4--4 of FIG. 3 showing thetemplate surface contour; and

FIG. 5 is a plan view partially broken away of an alternate embodimentof the invention suitable for use with various tool carriers.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to the drawings, FIG. 1 illustrates a first embodiment ofthe invention. As seen in this Fig., a belt 10 having overlapping ends11, 12 has a central region generally designated with numeral 14. Inregion 14, the edges of the belt curve outwardly to a maximum widthdimension at essentially the center of region 14. The two overlappingends 11, 12 are provided with complementary hook and eye fasteners inorder to provide an adjustable closure for the belt. A secondary closureis provided by additional belting 16, 17 of reduced width. The belt 10can be fabricated from any suitable material, such as a Nylon fabric andis preferably a two-ply belt secured around the perimeteral edges so asto enable the retention therewithin of an orthopedic pad illustrated inFIGS. 2-4.

FIG. 2 illustrates the embodiment of FIG. 1 secured about the abdomen ofa user shown in broken lines with the orthopedic pad 20 in place in thelower back region of the user. The belt 10 is fabricated with alongitudinal taper obtained by providing the belt with a shorter lengthalong the top edge than along the bottom edge. As a consequence, thepad, when installed, resides at an angle 21 with respect to a verticalline drawn perpendicular to the circumference of the user's waist, sothat the pad 20 will nest against the lordotic curve of the wearer.

As seen in FIGS. 3 and 4, pad 20 has a pair of opposing straight edgeportions 22, 23 which are joined by the arcuate perimeteral edges 25,26. Each arcuate perimetral edge 25, 26 has a convex curvature whichreaches a maximum deviation from the mid-point at approximately thelongitudinal center of the pad. As best shown in FIG. 4, the pad has asubstantially flat base portion 27 and a working surface 29 termed thetemplate surface herein. The template surface 29 has a central depressedregion 30 conforming to the spinal portion of the user's back. Flankingboth sides of central hollow region 30, which extends from the top tothe bottom edges 25, 26, are a pair of plateau regions 32, 33 arrangedto contact the erector spinae muscles of the wearer's back. Each plateauregion tapers downwardly in the outward direction to an essentially flatregion 34, 35. Each of the flat regions 34, 35 then blends into therespective edge 23, 22. A plurality of ventilation holes 38 are formedthrough the pad 20.

The pad 20 is made from any suitable stiff but resilient material whichwill provide a non-conforming contour to the wearer's lower back regionunder normal use and in the absence of excessive forces. The preferredmaterial for pad 20 is ethylene vinyl acetate having the followingcharacteristics:

    ______________________________________                                        hardness             38° ± 3                                        density              0.26 gm/cc.                                              tensile strength     7                                                        elongation           400%                                                     blowing              11                                                       ______________________________________                                    

The pad has an ovalized center region having a maximum length of aroundeight inches and a minimum width of about four inches. The plateauregions 32, 33 are spaced from the central hollow 30 by approximatelyone and a half inches and have a maximum thickness of about one andone-eighth inch. The thickness in the hollow region 30 is aboutthree-quarter inch, and this hollow bridges the protruding spinalprocesses of the wearer. The raised surface areas 32, 33 approximate theaverage lordotic curve of a wearer, which greatly assists in maintainingproper posture.

In use, the pad 20 is installed within the belt 10, and the belt isarranged about the waist of the user as suggested in FIG. 2. When inplace, the pad 20 rests at an angle 21, which may be about 7°, with thetemplate surface 29 of the orthopedic pad 20 resting against thewearer's back in the lower back region. The plateau regions 32, 33 makesurface contact with the erector spinae muscles of the wearer throughthe skin, and the central hollow region 30 accommodates the bonyprotrusions of the spine. The pad responds to extension of the back awayfrom the idealized posture represented by the template surface byopposing such extension due to the relative stiffness of the material.Flexion is opposed by the natural tendency of the proprioceptors of theback to adapt to and follow a smooth surface.

It should be noted that, during muscle relaxation, the pad 20 moves awayfrom the spine as an integral unit which allows the muscle and ligamentstructure of the back to provide its own support. This tends tosubstantially reduce or eliminate atrophy of the back muscles.

FIG. 5 illustrates an alternate embodiment of the invention which isespecially suitable for use as a workman's orthopedic device. As seen inthis Fig., the belt is provided with a plurality (three illustrated) ofsecondary belt loops 41, 42 and 43. These loops are attached to the mainbelt 10 in any suitable fashion, such as by stitching at appropriateintervals, and provide guideloops for a secondary belt 45. Secondarybelt 45 serves as a belt support for tool holsters such as the holsters46, 47 illustrated in broken lines. The holsters 46, 47 may be of anysuitable design for carrying the tools of interest to a particularworkman, such as pliers, screwdrivers, wire cutters, hammers, etc. Theholsters are attached by threading the secondary belt 45 through theholster flaps. The belt 10 shown in FIG. 5 uses the same orthopedic pad20 as that described above.

As will now be apparent, the invention provides an effective orthopedicsupport for the lower back region of a wearer. The device is convenientin use and inexpensive to manufacture. The pad is arranged at the properangle when the belt is installed so as to approximate the averagelordotic curve of a user.

While the above provides a full and complete disclosure of the preferredembodiment of the invention, various modifications, alternateconstructions and equivalents will occur to those skilled in the art.For example, although specific materials have been described withreference to the belt, the closure and the pad, other equivalentmaterials may be employed, as desired. Therefore, the above descriptionsand illustrations should not be construed as limiting the scope of theinvention which is defined by the appended claims.

What is claimed is:
 1. For use with a lumbosacral support system, aunitary orthopedic pad having an upper margin, a lower margin, and apair of oppositely disposed end margins, said upper and lower marginseach extending between said end margins, said upper and lower marginseach having a curved profile, the separation distance between said upperand lower margins increasing in magnitude inwardly from the end marginsto a maximum value in a central region, said pad having a smoothlycontoured template surface bounded by said margins with a central troughportion extending between said upper and lower margins for accommodatingthe spinal processes of a wearer when the pad is pressed against thelumbar region, and a pair of raised plateau regions flanking saidcentral trough portion for contacting the erector spinae muscles of thewearer to provide support therefor, the template surface of said padhaving a smoothly curving, physiologically nonconforming surface contourthrough the central region thereof approximating the lordotic curve of awearer, to assist maintaining proper spinal posture.
 2. The invention ofclaim 1 wherein said pad is fabricated from a compressed foam material.3. The invention of claim 1 wherein said pad is fabricated from ethylenevinyl acetate.
 4. The invention of claim 3 wherein said template surfacehas a hardness of between about 35 and about 41 degrees.
 5. Theinvention of claim 1 wherein said pad has a maximum width in the area ofthe central trough portion of substantially nine inches and top andbottom edges having a convex curvature.
 6. The invention of claim 5wherein said pad has a thickness in the raised plateau regions ofapproximately one and one eighth inches.
 7. The invention of claim 5wherein the maximum thickness of said pad in the central trough portionis approximately three-quarter inch.
 8. An orthopedic pad, for use witha lumbosacral support system, comprising:a body having curved upper andlower edges, the edges having central regions and end regions, thedistances between the upper and lower edges at the center regions beinggreater than at the end regions; the body having a template surface,adapted to press against the lumbosacral region of the user, having avertically oriented central trough region and a pair of raised plateauregions flanking the central trough region for contacting the erectorspinae muscles of the user; and the raised plateau regions of thetemplate surface having a smoothly curving, physiologicallynonconforming surface contour approximating the lordotic curve of theuser so to assist maintaining proper spinal posture.
 9. The pad of claim8 wherein the body is a one-piece stiff foam body.
 10. The pad of claim8 wherein the raised plateau regions of the template surface are of astiff foam material having a hardness of about 35° to 41°.
 11. Anorthopedic pad, for use with a lumbosacral support system, comprising:aone-piece stiff foam body having curved upper and lower edges, the edgeshaving central regions and end regions, the distances between the upperand lower edges at the center regions being greater than at the endregions; the body having a template surface, adapted to press againstthe lumbosacral region of the user, having a vertically oriented centraltrough region and a pair of raised plateau regions flanking the centraltrough region for contracting the erector spinae muscles of the user;and the raised plateau regions of the template surface having a smoothlycurving, physiologically nonconforming surface contour approximating thelordotic curve of the user so to assist maintaining proper spinalposture, the raised plateau regions of the template surface having ahardness of about 35° to about 41°.